Manually operable tool for setting tubular rivets



Dec. '26, 1967 5 DlMAlo 3,359,778

MANUALLY OPERABLE TOOL FOR SETTING TUBULAR RIVETS Filed Oct. 18, 1965 -m ee... Q INVENTOR Q Q Q ANTHONY E. DIMAIO WQQZZ YQQSQ ATTOR N EYS United States Patent 3,359,778 MANUALLY OPERABLE TOOL FOR SETTING TUBULAR RIVETS Anthony E. Di Maio, Georgetown, Mass., assignor to Marson Fastener Corporation, Chelsea, Mass., a corporation of Massachusetts Filed Oct. 18, 1965, Ser. No. 496,807 2 Claims. (Cl. 72-391) The present invention relates to fastener setting tools and, more particularly, to tools of the type adapted to set tubular rivets into an apertured structure that may be accessible from one side only. Such a tubular rivet, for example, comprises: an external tubular member of relatively ductile material having a preformed flange at the rearward end of the rivet; and an internal mandril member having a head engaging the tubular member at the forward end of the rivet and a stem projecting through the rearward end. In operation, first the forward end of the rivet is inserted through the aligned holes of a pair of work pieces to be joined with the preformed flange abutting against the outer face of one of the workpieces. Next the stem is gripped by a tool and retracted through the rearward end in such a way that the head deforms the tubular member at the forward end of the rivet to provide a new formed flange abutting against the outer face of the other of the workpieces. Finally continued retraction of the mandril member, when the new formed flange sufiiciently resists further endwise movement, causes a rupture within the tubular member of an expendable portion of the mandril member from the remainder, thereby leaving the rivet set into position and free of the tool.

'The present invention contemplates a novel operable rivet setting tool characterized by an arrangement by which certain mandril gripping elements and certain manually actuated elements are isolated from each other for eflicacious operation. The present invention further contemplates a particular construction that permits the use of varied sizes of mandrels so that the rivet setting tool may be used to apply rivets of more than one size without change of internal parts.

The primary object of the present invention is to provide a rivet setting tool comprising a pair of handles pivoted to each other at a first center, a slider bracket that is pivoted to one of the handles at a second center and that presents an integral jaw, and a rocking jaw that pivots in the slider bracket between a position of engagement with the integral jaw when the handles are closed and a position of disengagement with the integral jaw when the handles are opened, an import-ant feature of the invention being a particular construction of the rocking jaw, which may be biased toward engagement with the integral jaw in such a manner as to operate effectively with mandrels of various diameters.

Other objects of the present invention will in part be obvious and will in part appear hereinafter.

The invention accordingly comprises the device involving the components and relationships exemplified in the following detailed disclosure, the scope of which will be indicated in the appended claims. For a fuller understanding of the nature and objects of the present invention, reference should be had to the following detailed description, taken in connection with the accompanying drawings, wherein:

FIG. 1 is a broken away view of operative components of a preferred rivet setting tool of the present invention;

FIG. 2 is a fragmentary detail of the rivet setting tool at the beginning of a typical riveting operation;

FIG. .3 is an exploded view of certain components of the rivet setting tool; and

3,359,778 Patented Dec. 26, 1967 ice FIG. 4 is a side elevation of the rocking jaw of the rivet setting tool.

Generally, as best shown in FIG. 1, the illustrated rivet setting tool comprises: a manual control and encasing support assembly in the form of a pair of handles 20, 22, which are pivoted about a main center 24 to each other. Handles 20 and 22 both are of sheet metal fold construction in the form of channel-like portions that extend forwardly to house and support the mandrel actuating parts. One of the handles provides an anvil bore 26 through which the mandril of the rivet (to be described below) may be inserted, and a mandril gripping and rupturing assembly in the form of a slider bracket 28, which is pivoted about an eccentric center 30 at its upper extremity and provides an integral jaw 32 that is fixed with respect thereto, and a rocking jaw 34 that is pivotable with respect thereto. Attached to the lower handle and pivotally connected thereto by a thumb screw 19 is a turret 21 with two holes 23 and 25 capable of alignment with anvil base 26 for piloting a mandrel into operating position. The turret shown in FIG. 1 is in the form of a flat plate with cups at the extremities thereof in which holes 23 and 25 are provided.

A fragmentary detail view of the rivet setting tool at the beginning of a typical riveting operation is shown in FIG.

2. A typical rivet for use with the tool of the present invention is shown for use in connecting a pair of workpieces 11, 12 that are apertured by aligned holes. The rivet is shown as including a mandril 14 surrounded by a tube 15. Tube 15 is composed of a relatively soft metal such as soft steel, and mandril 14 is composed of a relatively hard metal such as hard steel. Mandril 14 is provided at one extremity with a head 16 that abuts against the forward part of tube 15 and is provided at the other extremity with a stem portion that extends rearwardly from tube 15. The stem portion is separated from head 15 by a constriction 18 which constitutes a weakened point at which the mandril ruptures when a predetermined tensile force is exceeded.

FIG. 3 is an exploded view of the slider bracket, the rocking jaw, and the pins and shafts appurtenant thereto. Slider bracket 28 is shown as including a pair of spaced channel sections 82, 84, which are integrally connected at a connecting bite constituting integral jaw 32. The upper narrower extremities of sections 82, 84 are provided with bearing holes 86, 88. The lower, wider extremities of sections 82, 84 are provided with pairs of pin holes 90, 92. Extending through and between pairs of pin holes 90, 92 are a pair of pins 94, 96. Rocking jaw 34 is positioned Within and between channel sections 82, 84, being provided with a journal hole snugly receiving pin 94 and a limit hole 98 through which pin 96 projects. Limit hole 98 is considerably larger in diameter than pin 96 in order to permit rocking of rocking jaw 34. As will be observed in FIG. 1, a shaped leaf spring 104, having opposed sections 106, 108 and hook extremities, operates between a notch 114 in rocking jaw 34 and an abutment 113 formed by bosses biased inwardly and in line in the pair of channel sections 82 and 84. Bracket 28 .is guided for reciprocal motion by a lug 116 struck from the bight of handle 22.

FIG. 4 is a side elevation showing the unique construction of rocking jaw 34. The pitch of the teeth is on a radius 35 taken from a point 37 higher and more rearwardly than the pivot point of the rocking jaw which is at the center of pin 94 in its normal operation. By way of example, in the present rocking jaw 34 shown in FIG. 4, the center point 37 of the radius 35 is in a more rearwardly position than the center of pin 94 by an amount equivilant to approximately one-fifth of the length of the radius. Also, the center point 37 is in a more upwardly position than the center of pin 94 by an amount equivalent to approximately one-third the length of the radius. As a result, this forms a larger arc of effective bite. The teeth of the rocking jaw can therefore engage a wider range of diameters of mandrels, while it pivots on the same axis of pin 94.

The detail view of FIG. 4 emphasizes certain important features of rocking jaw 34, which as indicated above is pivoted about a center 94. The teeth of rocking jaw 34 are generated along an are that is eccentric with respect to center 94 in order to eifect a bite with integral jaw 32 when mandrel 14 is to be pulled. It has been found that if this arc has too much eccentricity the teeth will cut through the mandril when pulled. On the other hand if this are has too little eccentricity, the teeth will not hold the mandrel after it has separated from its stern, and the mandril will tend to be propelled from between the jaws in a dangerous manner. Rocking jaw 34 is shown as having dimensions for accommodating three typical hard steel mandrils having approximately the following diameters; diameter of first mandril=approximately .096 to .097; diameter of second mandril=.114 to .115; and diameter of third rivet=.076 to .077. Hole 23 of turret 26 accommodates the mandril of the third rivet. Hole 25 of turret 26 accommodates the mandrils of the first and second rivets. In FIG. 4, the center of the radius of curvature of the toothed arc of rocking jaw 34 is shown at 37. Center 37 is shown as being spaced from center 94 by a distance and at an orientation defined by two perpendicular lines segments a and b. The radius of the toothed arc is designated r. These dimensions, which are critical are as follows; a=.250 to .500"; b=.l25 to .375"; and r=1.l to 1.300". The example shown: a=.375"; b=.250"; and r=1.175.

In operation, normally spring 104 serves to cause rocking jaw 34 to abut against the profile boundary in the vicinity of anvil bore 26. When a rivet mandril is inserted into position between integral jaw 32 and rocking jaw 34 it is maintained in that position by light pressure exerted by spring 104 in such a way as to prevent its dropping out of anvil bore 26. Nevertheless this tubular rivet may be manually pulled from anvil bore 26. When the handles are moved to their outermost position, the insertion of a new mandril stem forces the old previous mandril stem out from between the jaws for ejection from within the tool through the opening adjacent to the slider bracket and the forwardly portion of the rivet setting tool. When handles 20, 22 are manually closed into position shown in FIG. 1, slider bracket 28 is lifted by the eccentirc action of centers 24, 30 in such a way as to cause the mandril stem to be securely gripped between integral jaw 32 and rocking jaw 34.

The present invention thus provides a novel rivet setting tool which conveniently holds several diameters of mandril stems in position before, during and after setting of the rivet. Since certain changes may be made in the foregoing disclosure without departing from the scope of the invention herein, it is intended that all matter described in the foregoing specification and shown in the accompanying drawings be interpreted in an illustrative and not in a limiting sense.

What is claimed is:

1. A rivet setting tool capable of setting rivets of a plurality of diameters, each rivet having an external tubular element and an internal rupturable mandrel element, said rivet setting tool comprising a pair of handles pivoted to each other about a main handle center, a slider bracket pivoted to one of said handles about an eccentric handle center spaced from said main handle center, a housing on the other of said handles providing an anvil aperture, a turret pivotally attached to said housing providing a plurality of apertures any one of which may be moved into alignment with said anvil aperture, said slider bracket providing an integral jaw, a rocking jaw pivotally moveable about a main jaw center between positions remote from and adjacent to said integral jaw, said rocking jaw having a set of teeth arranged in an are about an eccentric jaw center and biased toward said stationary jaw, said eccentric jaw center being spaced from and oriented to said main jaw center by two line segments at right angles to each other, the first line segment extending from said main jaw center a distance of approximately .250 to .500, the second line segment extending from said eccentric jaw center a distance of approximately .125 to .375", the radius of said arc being approximately from 1.100 to 1.300", a spring urging said rocking jaw into the position adjacent to said integral jaw, an abutment on said other of said handles limiting movement of said rocking jaw toward said integral jaw when said handles are opened, said rocking jaw being free of said abutment when said handles are closed, said rocking jaw and said stationary jaw being operative in alignment with said anvil aperture, said slider bracket including parallel channel sections, a pair of stationary pins extending between the channel sections, the bite between the channel sections constituting said stationary jaw, a journal hole in said rocking jaw pivotally receiving one of said pins, a limit hole of larger diameter than the other of said pins receiving said other of said pins.

2. A rivet setting tool capable of setting rivets of a plurality of diameters, each rivet having an external tubular element and an internal rupturable mandril element, said rivet setting tool comprising a pair of handles pivoted to each other about a main handle center, a slider bracket pivoted to one of said handles about an eccentric handle spaced from said main handle center, a housing on the other of said handles providing an anvil aperture, 9. turret pivotally attached to said housing providing a plurality of apertures any one of which may be moved into alignment with said anvil aperture, said slider bracket providing an integral jaw, a rocking jaw pivotally moveable about a main jaw center between positions remote from and adjacent to said integral jaw, said rocking jaw having a set of teeth arranged in an are about an eccentric jaw center and biased toward said stationary jaw, said eccentric jaw center being spaced from and oriented with respect to said main jaw center by two line segments at right angles to each other, a spring urging said rocking jaw into the position adjacent to said integral jaw, said rocking jaw and said stationary jaw being operative in alignment with said anvil aperture, said slider bracket including parallel channel sections, the bite between the channel sections constituting said stationary jaw, means along the first line segment extending from said main jaw center and means along the second line segment extending from said eccentric jaw center cooperating with said turret to enable proper gripping of any mandril elements operationally fitting into any of said plurality of apertures.

References Cited UNITED STATES PATENTS 3,154,210 10/ 1964 Elliott 72391 FOREIGN PATENTS 1,116,324 1/1956 France.

542,3 82 1/ 1942 Great Britain.

CHARLES W. LANHAM, Primary Examiner, G. P. CROSBY, Assistant Examiner, 

1. A RIVET SETTING TOOL CAPABLE OF SETTING RIVETS OF A PLURALITY OF DIAMETERS, EACH RIVET HAVING AN EXTERNAL TUBULAR ELEMENT AND AN INTERNAL RUPTURABLE MANDREL ELEMENT, SAID RIVET SETTING TOOL COMPRISING A PAIR OF HANDLES PIVOTED TO EACH OTHER ABOUT A MAIN HANDLE CENTER, A SLIDER BRACKET PIVOTED TO ONE OF SAID HANDLES ABOUT AN ECCENTRIC HANDLE CENTER SPACED FROM SAID MAIN HANDLE CENTER, A HOUSING ON THE OTHER OF SAID HANDLES PROVIDING AN ANVIL APERTURE, A TURRET PIVOTALLY ATTACHED TO SAID HOUSING PROVIDING A PLURALITY OF APERTURES ANY OF WHICH MAY BE MOVED INTO ALIGNMENT WITH SAID ANVIL APERTURE, SAID SLIDER BRACKET PROVIDING AN INTEGRAL JAW, A ROCKING JAW PIVOTALLY MOVEABLE ABOUT A MAIN JAW CENTER BETWEEN POSITIONS REMOTE FROM AND ADJACENT TO SAID INTEGRAL JAW, SAID ROCKING JAW HAVING A SET OF TEETH ARRANGED IN AN ARC ABOUT AN ECCENTRIC JAW CENTER AND BIASED TOWARD SAID STATIONARY JAW, SAID ECCENTRIC JAW CENTER BEING SPACED FROM AND ORIENTED TO SAID MAIN JAW CENTER BY TWO LINE SEGMENTS AT RIGHT ANGLES TO EACH OTHER, THE FIRST LINE SEGMENT EXTENDING FROM SAID MAIN JAW CENTER A DISTANCE OF APPROXIMATELY .250 TO 